calm
good-natured
affliction
at rest
bane
besetment
bother
botheration
cloistered
collected
composed
contented
cool
coolheaded
curse
detached
disease
dwindling
easy
easygoing
ebbing
epidemic
even-tenored
exasperation
gentle
halcyon
hushed
impassive
inexcitable
infestation
invasion
irenic
irritant
isolated
moldering
nuisance
outbreak
pacific
peaceable
peaceful
pes
pest
pestilence
philosophical
plague
pleased
poised
quiescent
quiet
amiable
bland
complacent
courteous
dreamy
sedate
sunny
tranquil
unruffled
acid
antacid